Temperatures could drop to lows of 20 to 24 overnight Tuesday and stay below freezing for 10 to 14 hours. That would shatter low temperature records of 31 degrees in downtown Charleston, set in 1903; and 27 degrees at the airport, set in 1949, Lock said.

A long-duration hard freeze will kill sensitive vegetation and could cause poorly insulated pipes to freeze and burst, forecasters say.

The National Weather Service urges residents to bring pets inside, protect outdoor plants and cover and insulate unprotected plumbing.

Temperatures should climb back up toward the 70s with a nice warming trend by the weekend, but possibly with another dose of rain, Lock said.